For availability and the option of picking your tuner I suggest Hondata. An extra $200 for a Hondata isn't going to kill any turbo budget.


And stay 75mm if you can. What's the point of going an extra 0.5mm and a reaping stuff-all extra displacement when you can add more boost instead? Not worth the hassle of buying oversized pistons and rings, boring out the cylinders etc. If you need to go oversized because the cylinders are out of round that's another story. Otherwise don't waste your time. Just get some good strong rods, or even just cryogenically treat them + your pistons.